Representative Steve J. Israel, Democrat of New York, also called on Mr. Weiner to step down, saying that he clearly needed to seek treatment for “inappropriate behavior.”

“I pray for his family and hope that Anthony will take time to get the help he needs without the distractions and added pressures of Washington,” Mr. Israel said.

At the same time, two senior Democratic officials said on Saturday that Mr. Weiner was planning to check himself into a treatment center.